Shoulder Impingement Syndrome Treatment & Management

Updated: Oct 23, 2018
  • Author: Thomas M DeBerardino, MD, FAAOS, FAOA; Chief Editor: Craig C Young, MD  more...
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Acute Phase

Rehabilitation Program

Physical Therapy

The goals of the acute phase are to relieve pain and inflammation, prevent muscle atrophy without exacerbating the pain, reestablish nonpainful range of motion, and normalize the arthrokinematics of the shoulder complex. This includes a period of active rest, eliminating any activity that may cause an increase in symptoms.

Range-of-motion exercises may include pendulum exercises and symptom-limited, active-assisted range-of-motion exercises. Joint mobilization may be included with inferior, anterior, and posterior glides in the scapular plane. Strengthening exercises should be isometric in nature and work on the external rotators, internal rotators, biceps, deltoid, and scapular stabilizers (ie, rhomboids, trapezius, serratus anterior, latissimus dorsi, pectoralis major). Neuromuscular control exercises also may be initiated.

Modalities that also may be used as an adjunct include cryotherapy, transcutaneous electrical nerve stimulation, high-voltage galvanic stimulation, ultrasound, phonophoresis, or iontophoresis.

Patient education regarding activity; pathology; and the avoidance of overhead activity, reaching, and lifting is particularly important for this acute phase. The general guidelines to progress from this phase are decreased pain or symptoms, increased range of motion, painful arc in abduction only, and improved muscular function.

A systematic review and meta-analysis by Steuri et al found that although the quality of evidence was low, exercise interventions should be considered for all patients with shoulder impingement symptom. [4]

A study of 97 patients on the waiting list for subacromial decompression reported that an exercise program that included eccentric exercises for the rotator cuff and a combination of concentric and eccentric exercises for scapula stabilizers, lowered surgical rate and resulted in decreased symptoms. These results were also maintained on 1 year follow-up. [5]

Extracorporeal shock wave therapy has also been used in subacromial impingement syndrome. A study by Santamato et al indicated that a combination of extracorporeal shock wave therapy and isokinetic exercise is more effective than shock wave therapy alone for treatment of the condition. [6]

A study by Keenan et al indicated that kinesiology taping in subacromial shoulder impingement syndrome neither improves nor impairs shoulder strength, shoulder proprioception, or scapular kinematics. [7]

Subacromial injection

During the acute to subacute phase, when pain and inflammation are predominant, a subacromial injection may be diagnostic and therapeutic as an adjunct to a rehabilitation program. Injection of 10 mL of 1% lidocaine solution (without epinephrine) into the subacromial space should relieve shoulder pain if pain and inflammation truly is originating from the supraspinatus outlet/subacromial space. Adding a low dose intermediate-acting injectable corticosteroid may provide a therapeutic effect. Betamethasone, triamcinolone, and methylprednisolone commonly are used. One mL of any of these available injectable corticosteroids mixed with 9 mL of 1% lidocaine solution (without epinephrine) commonly is used.

One clinical trial found that subacromial injection of corticosteroid provided effective relief of symptoms and normalized function in patients with impingement syndrome. The authors noted that ultrasound-guided injections were not significantly better than a standard clinical injection when performed by an experienced individual. Injection accuracy, measured by post-injection MRI, was unexpectedly low for both blind and ultrasound-guided techniques (65% versus 70% respectively). [8]

A recent Cochrane review concluded that there is currently insufficient evidence to recommend the use of platelet-rich therapy (PRT) preparations for the treatment of impingement syndrome. [9]

Technique: Have the patient sit with the arm hanging by his/her side to distract the humerus from the acromion. Identify the lateral edge of the acromion. Insert the needle at midpoint of acromion and angle slightly upward under the acromion to full length. Slowly withdraw needle while simultaneously injecting fluid in a bolus wherever resistance is not present. Continue aspirating before injecting. Sometimes a swelling caused by fluid is visible around the edge of the acromion. Occasionally, calcification occurs within the bursa and hard resistance is encountered. In this case, aspiration and infiltration with a large bore needle and local anesthetic may be helpful. Failure of this injection may necessitate surgical evaluation.

Aftercare: Patient is informed that a local reaction may occur to the corticosteroid in the next 24-72 hours once the effect of the lidocaine wears off. If this happens, the patient is recommended to apply ice (wrapped in a towel) to the affected shoulder 20 minutes on and 20 minutes off, 3 times at the beginning and end of the day. Relief of pain after one injection is usual, but the patient must be advised to maintain correct posture with retraction and depression of the shoulder and to avoid the painful arc of elevation for 1 week. Patient may resume a symptom-limited therapy program in the first week postinjection, and then resume the full course.

Adverse effects of medications may be minimized when dosed as recommended. Adverse reactions are uncommon; however, they may occur, even when the injection is administered correctly. The clinician and patient must be educated about possible reactions, and the clinician must know how to manage any related complications. Absolute contraindications include documented allergy to any corticosteroid or local anesthetics. Relative contraindications include diabetes, hypertension, immunosuppression, cardiac arrhythmias, and heart blocks.

Adverse effects of injectable corticosteroids

  • Systemic effects include flushing, menstrual irregularity, impaired glucose tolerance, osteoporosis, psychological disturbance, steroid arthropathy, steroid myopathy, and immunosuppression.

  • Local effects include postinjection flare.

Adverse effects of local anesthetics

  • Usually, adverse effects are due to overdose and allergic reactions, which definitively can be minimized by double-checking the administered dose and inquiring about and checking on medication records for medication allergies.

  • Effects of overdose and allergic reactions may be catastrophic and may include cardiac, respiratory, and cerebral compromise.

Adverse reaction to the injection: Occasionally, a patient may experience a vasovagal reaction (faint) due to pain, apprehension, or needle phobia. In such cases, treatment should consist of the following:

  • Lie the patient down in the supine position. Elevate the patient's legs.

  • Strongly reassure patient that recovery is fast.

  • If patient briefly loses consciousness, protect the airway and give oxygen at 35% concentration.

High-intensity laser therapy

Santamato et al evaluated the short-term effects between high-intensity laser therapy (HILT) and sonographic therapy in 70 patients with subacromial impingement syndrome. [10] The patients were randomized to receive 10 treatments of HILT or ultrasound over 2 consecutive weeks. After 2 weeks, patients in the HILT group showed statistically significant improvements in pain reduction, articular movement, functionality, and muscle strength as measured by 3 outcome measure scores. [10] However, further investigation is warranted, as the study was limited by its small size, lack of control or placebo groups, and follow-up period.

Surgical Intervention

In general, conservative measures are continued for at least 3-6 months or longer if the patient is improving, which is usually the case in 60-90% of patients. If the patient remains significantly disabled and has no improvement after 3 months of conservative treatment, the clinician must seek further diagnostic work-up, as well as reconsider other etiologies or refer for surgical evaluation.

Appropriate surgical referrals are patients with subacromial impingement syndrome refractory to 3-6 months of appropriate conservative treatment. Surgery may be particularly beneficial in patients with full unrestricted PROM, positive response to injection of lidocaine into the subacromial space, a type III acromion having a large subacromial spur and those in whom changes are noted in the rotator cuff tendon on MRI scanning.

In a systematic review, Dorrestijn et al attempted to compare the effects of conservative and surgical treatment for subacromial impingement syndrome with regard to improvement of shoulder function and reduction of pain. [11] Of 4 randomized controlled trials that met the investigators' criteria, 2 were of medium methodologic quality and 2 were of low methodologic quality, but there were no differences in outcome between the treatment groups. Their findings led Dorrestijn et al to note the scarcity of high-quality randomized controlled trials does not allow conclusive evidence for differences in pain outcomes and shoulder function in conservatively and surgically treated patients with subacromial impingement syndrome. [11]

In another study, Ketola et al found no evidence that arthroscopic acromioplasty provides any additional value in the treatment of shoulder impingement syndrome. [12] In a randomized, controlled trial in 140 patients, follow-up at 24 months showed no statistically significant difference in self-reported pain between patients who received only a supervised exercise program and those who underwent acromioplasty followed by an exercise program. In addition, acromioplasty added considerably to the cost of treatment. [12] A review article found no significant difference between outcomes of formal bony subacromial decompression compared with an isolated subacromial bursectomy. [13]

Surgical evaluation

Initial examination under anesthesia (general anesthesia vs. regional block) and diagnostic arthroscopy

Evaluation of shoulder ROM and stability

In patients with limited motion, manipulation of the shoulder is performed. Diagnostic arthroscopy also may be performed, but arthroscopic subacromial decompression is generally not performed in patients with significant preoperative stiffness due to the increased risk of postoperative adhesive capsulitis.

Document any instability.

Arthroscopic evaluation

Particular attention is directed to the rotator cuff, especially the supraspinatus tendon near its insertion onto the greater tuberosity

Visualize the subscapularis tendon.

Assess for labral pathology or changes suggesting glenohumeral instability.

A partial tearing of the supraspinatus tendon along its articular surface is a common finding in symptomatic throwing athletes. The fragmented and torn tissue is debrided, leaving all intact rotator cuff tendon. This allows a more accurate determination of the size and thickness of the tear on the articular side of the rotator cuff and may help reduce symptoms of catching and pain.

Following glenohumeral arthroscopy, the bursal side of the rotator cuff is then evaluated with arthroscopy

The bursal surface of the rotator cuff is assessed for evidence of fraying as well as the amount of clearance between the anterior inferior acromion and the supraspinatus tendon.

Also noted are any signs of fraying or wear changes on the undersurface of the coracoacromial ligament.

If no evidence of rotator cuff disruption is noted, the coracoacromial ligament is smooth with adequate space between the anterior inferior acromion and rotator cuff, then the diagnosis of subacromial impingement is unlikely. In this case, subacromial decompression is not performed.

In case of a small partial-thickness rotator cuff tear on the articular surface, without evidence of impingement, only glenohumeral debridement of this tear is performed. However, if the patient has changes suggestive of impingement syndrome, arthroscopic subacromial decompression (acromioplasty- resection of the anterior inferior portion of the acromion) is performed as well.

If following subacromial decompression, a rotator cuff repair is necessary, it may be continued with arthroscopic assistance or it may be necessary to convert the rotator cuff repair to an open procedure.

Postoperative care

Postoperatively, a radiograph (supraspinatus outlet view) should be obtained to document the adequacy of the subacromial decompression. The appearance on this radiographic view should be of a type I acromial arch without any residual spurring.

Following subacromial decompression, the patient is placed in a sling but is encouraged to remove the sling when comfortable and begin AROM and PROM exercises. When pain has decreased significantly and ROM has returned toward normal, a program of strengthening similar to the previously mentioned conservative management may be instituted. Patients cannot begin sports-specific activities until they have full AROM in the operated shoulder and normal strength, generally a time course of approximately 3-4 months.

Surgical outcome

Results are generally good for properly selected middle-aged patients with evidence of impingement on history and physical examination and at the time of arthroscopy.

General consensus in the literature is that arthroscopic subacromial decompression results in a good return to the previous level of function in approximately 85-90% of patients; however, results are generally poor in young high-performance athletes who participate in overhead activities.

Recent evidence in the literature reveals the limited utility of isolated subacromial decompression for the treatment of recalcitrant shoulder impingement syndrome. [14]



Recovery Phase

Rehabilitation Program

Physical Therapy

Initial goals of this phase are to normalize ROM and shoulder arthrokinematics, perform symptom-free daily activities, and improve neuromuscular control and muscle strength. ROM exercises should progress to active exercises in all planes and self-stretches, concentrating on the joint capsule, especially the posterior capsule.

Strengthening exercises should include isotonic dumbbell resistance exercises with the supraspinatus, internal rotators, external rotators, prone extension, horizontal abduction, forward flexion to 90°, upright abduction to 90°, shoulder shrugs, rows, push-ups, press-ups, and pull-downs to strengthen the scapular stabilizers. Joint mobilization and neuromuscular reeducation also should be maintained. Upper extremity ergometry exercises, trunk exercises, and general cardiovascular conditioning should be maintained for endurance. Use of modalities may be continued if necessary. Guidelines to advance from this phase are full pain-free ROM and when manual muscle strength testing is 70% of the contralateral side.

The final goal of this phase is to get the athlete back to throwing and should include improving strength, power and endurance, and sports-specific neuromuscular control. Emphasis is placed on high-speed, high-energy strengthening exercises, and eccentric exercises in diagonal patterns. Continue isotonic strengthening with increased resistance in all planes, allowing resistance in the throwing position, 90° of abduction, and 90° of external rotation. Initiate plyometrics, sports-specific exercises, proprioceptive neuromuscular facilitation, and isokinetic exercises.


Maintenance Phase

Rehabilitation Program

Physical Therapy

The goal of this phase is to maintain a high level of training and prevent reoccurrence. Emphasis is placed on longer, more intense workouts and proper arthrokinematics of the shoulder. Analysis and modification of techniques and mechanics may reexacerbate symptoms. Make refinements in intensity and coordination. Patient education again is reemphasized, maintaining proper mechanics, strength, and flexibility and understanding the pathology. The patient also should have a good understanding of the warnings signs of early impingement and continue with a home exercise program with proper warm-up and strengthening techniques.